Parkinson’s disease is a progressive neurological disorder that primarily affects movement but can also cause sleep, mood, cognitive and autonomic symptoms. It develops as dopamine-producing nerve cells in parts of the brain become impaired or are lost.
Common symptoms
- Slowness of movement
- Muscle stiffness
- Tremor, often beginning on one side
- Balance and walking difficulties
- Reduced facial expression or softer speech
- Sleep problems, constipation or reduced sense of smell
- Depression, anxiety or cognitive changes in some people
Diagnosis
There is no single routine test that confirms Parkinson’s disease. Diagnosis is usually based on medical history and neurological examination. Imaging or laboratory tests may be used to exclude other causes of symptoms.
Treatment
There is currently no cure, but medicines can improve movement symptoms by increasing or mimicking dopamine activity. Physical therapy, occupational therapy, speech therapy, regular exercise and multidisciplinary care can help maintain mobility and independence. Selected patients may benefit from treatments such as deep brain stimulation.
When to seek medical care
Gradually developing tremor, stiffness, slowed movement or balance problems should be medically assessed. Sudden weakness, facial drooping, speech difficulty or other abruptly developing neurological symptoms require emergency assessment because they may indicate stroke rather than Parkinson’s disease.
Related topics
Sources and further reading
Last reviewed: 4 September 2026. This page provides general health information and does not replace individual medical assessment or treatment.